Stencil machine and stencil thebepob



I Aug. 18, 193 H. P. ELLIOTT Re. 18,151

STENCIL MACHINE AND STENCIL THEREFOR Original Filed Jan. 15. 1927 B 6 QATTORNEY Reiuucd Aug.-18, 1931 V UNITED STATES PATENT OFFICE EABION P.ELLIOTT, O! WLTEBTOWN, IASSAGHUSETTS, QSSIGNOR T ELLIOTT ADDRESSINGMACHINE GO IPANY, CORPORATION OF KAQfiAC'HUSETTB STENCIL MACHINE ANDSTENCIL T HEBEFOR Original Io. 1,687,448, dated August 2, 1927, SerialHo. 180,871,11ed January 18, 1827. Application (or reissue fled 111117,1981. Serial No. 549,801. 1

This invention relates to stencil printing machines and to stencilstherefor.

A common type of stencil adapted for use in a stencil printing machlnecomprisesa cardboard frame having a window therein which is occupied bya thin sheet of ste nc1l aper that bears an address or other 1nd1c 1a. 3common type of stencil prmtmg machine adapted to operate upon suchstencils comprises a stencil track and a pair of superposed rollers orsectors which engage the stencil and move it along the track into andout of printing position and simultaneously print therefrom. Thesuperimposed sectors are adapted to bear against the thin stencil sheetand press the stencil into intimate contact with the envelo or otherarticle to be rinted and also to rive the stencil forwar ly to eflectthe printing operation. Such'a typ:e of 80 stencil printing mac inc andstencil have en used for a number of years and have proven verysuccessful and form a simple. ap aratus for rapidly printing addressesand t e like. It sometimes happens however, that the free 15 movement ofthe stencil under the action of the driving rolls or sectors is impededeither because of undue friction in the track due to roughness of thestencils or from other reasons. Under such conditions an unusual and 80great driving force is applied to the thin stencil paper by the sectorsin engagement therewith and as a consequence the stencil sheet isruptured or is torn away from its frame so that the stencil is damagedand must be discarded.

It is an object of this invention to prevent the tearing of the stencilby roviding driving rolls or sectors of such 0 aracter, and a stencil tocooperate with said rolls of such character, that while the rolls orsectors-serve to press the thin stencil sheet into intimate contact withthe envelope as has heretofore been the case, the stencil sheet isrelieved of any material driving stress and the drive is bornepractically entirely by the stencil frame.

' Fig. 1 is a perspective view of a stencil showing the superimposedrinting sectors in holder 12 disposed at one end of the track.

printing machine constructed in accordance with the invention, parts ofthe machine unnecessar for the understanding of the invention eingomitted.

Fig. 2 is a perspective view of a stencil constructed in accordance withthe invention.

Fig. 3 is a sectional view taken through the stencil, guides thereforand paper on which the name and address are being printed,

positions assumed just be ore the instant of then engagement with thestencil and with the paper, and "before the stencil and aper have beenflexed into contact one wit the other.

Fi 4 is a view similar to Fig. 3 but showmg t e manner in which thestencil sheet is pressed against the envelope while the driv- 1n forceis exerted upon the stencil frame.- he stencil printing machineconstructed in accordance with this invention includes a stencil track10 alon which the stencils are adapted to be moved in successive orderfrom a SUPBI'IIIIPOSQd' pile contained in a stencil A reciprocatorystencil pusher 14 is arranged to move the lowermost stencils insuccessive order from the stencil holder in the track 10. A stencilreceiver 16 is disposed at the other end of the track and is adapted tocatch the stencils as they pass from the track. A pair of superposedrotatable printing sectors 18 and 20 are disposed on opposite sides ofand intermediate said track and are adapted to engage the forward end ofa stencil after it has been delivered into the track from the stencilholder, and "also to engage an interposed envelope or other article tobe printed, and move both conjointly to effect the printing 0 eration.The printed envelopes pass from tween the sectors and fall free therefrom while the stencils pass along the track 'into the holder. The lowerprinting sector 20 has an inflexible face and is rotatably supported ina spring-pressed'yielding frame 22 which permits the sector to bedisplaced in a vertical direction to accommodate envelopes of variousthicknesses. The upper or printing sector 18 is provided with a yieldingor rubber face 24 which is adapted to be con- 100 stantly inked; and thetwo segments are adapted to be simultaneously rotated by suitable meansnot necessarily escribed.

The stencil constructed in accordance with 5 this invention for use inthe aforesaid machine is shown in rspective in Fig.2 andincrosssectionin .3and4. Thestencil comprises a relative y thick andinflexible rectangular frame 26 com of cardboard, which frame is provied with an elonglated opening or window 28 therein. The ame is alsoprovided with a stron and relatively thin sheet 30 of paper stoc whichis disposed midway between the opposite flat faces of the frame andextends into the window '28 thereof on all sides for a substantialdistance, thereby to provide a strong yet flexible margin for saidwindow. Said margin is ar opening 32 and a formed with a rectan sheet ofthin and flexible stencil paper 34 is cemented to said sheet 30 to coverthe opening 32. The stencil sheet is adapted to hear anaddress or otherindicia and 18 adapted to be pressed onto the envelo ure, ereby topermit ink from the inked surface of the up r roll to pass through theindicia and be eposited upon the surface of the envelope.

Also in accordance with this invention both sectors-18 and are adaptedto exert a driying force on the frame 26 of the stencil to exclude thethin stencil sheet from the drive. To this end the lower sector 20 has awidth aterthan the width of the window 28 in t e stencil so that thesector overlies the window on both sides thereof and thus is caused toexert its driving force upon the strong margin of the stencil ratherthan 4. upon the thin stencil sheet. Theupper sector 18 has a widthgreater than the opening 32 in the margin sheet and is adapted tooverlie the openin on both sides and to hear u the margin eet and. toimpress-its driving force thereon thereby to preserve. the thin stencilsheet free from driving stresses.- 1 The sides of the sector 18 areadapted to be inset from the sides of the window 28. in the stencilframe so that there, is a substan- W tial extent of the marginal sheet30 free from contact with the sector that can flex or be moveddownwardly to permit the stencil sheet to be pressed into intimatecontact with the envelope a as illustrated in Figii The side or drivingedges of t e yielding face 24 of the upper sector. are adapted .to becompressed more than the intermediate portion of the face, which is indirect contact with the stencil sheet, thus causing the side to bear thestrongest and thus exert the mam driving force u n the marginal sheet 30rather than upon t e thin stencil sheet.

The stencil track 10 is adapted to hold the stencils in'the aforesaidrelation so that the 05 sectors are caused to exert their driving force.as the envelope at of Fi 4 in thev manner mdicated in this figat alltimes on the stencil frame rather than upon the thin stencil sheet. Thismangement, while simple, prevents the rupture of the thin stencil sheetthat frequently occurs with, the usual driving sectors which were soarranged that they engaged the .thin stencil sheet only, in spite ofcareful operation and adjustment of the stencil printing machine.

aim:

Y 1. The' combination of a stencil having a strong frame provided with awindow therein and a sheet of thin stencil paper attached to the frameover the window, a air of su rposed sectors ada ted to drive e stenc'besectors characterized h each having a width greater than the wid ofthe window in the stencil frame, and means for guiding the stencil inits movement between the sectors in such a manner that the sectors exerta driving pressure upon the strong frame of the stencil and maintain thetfzhin stencil paper free from the driving orce.

- 2. The combination of a stencil having a strong frame provided with awindow therein, a strong and thin flexible sheet connected with theframe and extended into the window midway between the opposite faces ofthe frame and providin a continuous flexible margin for the win ow, asheet of stencilpaper attached to said flexible margin, and a pair ofsuperposeddriving sectors adapted to drive the stencils between them,one of said sectors characterized by having a width greater than thewidth of said window and adapted to overlap the window on opposite sidesthereof and underlie the opposite sides of the frame, and said uppersector characterized by having a width sufiiciently at to overlie andbear upon the opposite si es of the flexible ma 'n of said windowwhereby to exert its driving force upon said flexible margin and thewidth being less than the width of the .window whereby to rovide anunengaged' wortion of the margin that is adapted to ex downwardly. l

3. The combination of a stencil having a stiff frame provided with awindow therein a thin sheet of stencil paper attached to sai frame'anddisposed within the window aproximately midway between the OXPOSltQ acesof said frame, and supe riving sectors adapted to en age and rive thestencil between them eac characterized by havin a width adapting them tooverlie said window and exert a driving force on the stencil frame onopposite sides of said window and to be free from substantial drivingengagement withsaid stencil sheet.

4. The combination of a stencil having a strong inflexible frameprovided with a window therein, a thin flexible stencil. sheet attachedto said frame over the window, and superposed driving sectors for saidstencils and adapted to engage and drive the stencil tween them, sai

45 upon toflex said stencil sheet and flexible between them andcharacterized b each haying a width greater than the wi th of sad windowand overl ing and exerting a driving force on the rame only of saidstencil 5 and preserving said thin stencil sheet free a from anysubstantial driving force.

5. The combination of a stencil having a strong inflexible frameprovided with a wmdow therein, a thin flexible stencil sheet attached tosaid frame over the window, and superposed drivin and printing sectorsfor said stencils and a apted to engage and drive the stencil betweenthem, said sectors characterized by each having a width greater than thewidth of said window and overlying and exerting a drivin force on theframe only of said stencil an preserving said thin stencil sheet freefrom any substantial driving force', one of said sectors furthercharacterized by having a yielding face adapted to flex said flexiblestencil sheet into said window while maintaining driving engagement withthe stencil frame.

6. The combination of a stencil having a strong inflexible rectangularframe provided with a window therein, a relativel thin strong andflexible sheet connected wit the frame and extended into the windowmidway between the opposite faces of the frame, said sheet having anopening therein and providin a continuous flexible margin for theopening, a thin sheet of stencil paper secured to said margin over theopening and a pair of superposed driving sectors ada ted to engage anddrive the stencil between t em, said lower sector characterized byhaving an unyielding face which overlaps the stencil window on bothsides thereof and said upper sector characterized by having a yieldingface which overlaps the aforesaid openin and has a width less than thewidth of said window and is adapted to bear upon said margin sheet onopposite sides of said opening and exert a driving force mainlytheremargin downwardly toward said lower sector while preserving saidstencil sheet free from any substantial driving force.

In testimony whereof I have signed my name to this specification.

HARMON P. ELLIOTT.

